CA2099809A1

CA2099809A1 - Prefabricated building panel

Info

Publication number: CA2099809A1
Application number: CA002099809A
Authority: CA
Inventors: Amos G. Winter, Iv
Original assignee: Individual
Current assignee: Individual
Priority date: 1992-04-30
Filing date: 1993-07-05
Publication date: 1995-01-06
Also published as: US5224315A

Abstract

ABSTRACT OF THE DISCLOSURE

An improved multi-layered panel, sometimes referred to as a stress skin panel, has a highly insulative multi-layered core located adjacent to one skin or alternatively located between two skins bonded to or otherwise rigidly affixed to the two outside surfaces of the core. The core of the multi-layered panal has a plurality of core layers which may be of the same or of different foam plastic materials. The layers of the core located adjacent to the panel skins provide a thermal barrier for the middle or second core layer which middle layer may be of a thermoplastic such as styrofoam and also may provide the means for bonding or securely affixing the panel skins to the surface of the multi-layered core. Borate, which is typically in the form of a powder (a borate compound used has been TlM-BOR? a product manufactured by U. S. Borax Corporation), may be incorporated, or encapsulated into selected layers or all of the layers of the panel core. Borates in the form of borate compounds similar to TlM-BOR? in an amount typically between about 2 weight percent and about 10 weight percent results in a core material which deters the entry of and the infestation of ants and other insects thereby enhancing an improving the usefulness of such prefabricated building panels. The addition of the borate compound has also been found to act as a fungicide and further, the flame retardant properties of the building panel are improved. Borate may be added, if possible, into the core material of any known prefabricated construction/building panel.
However, it is most advantageous and effective if the borate is added during the fabrication of the core of the panel.

Description

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~ AN IMPFIOVEC) PREFABRICATED BUILDING PANEL
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~ACK~P~OUN~ OF THE INV~hlTlON
This is a con~inuation-in-part of United States Patent Application serial number 07/876,9~0 filed 4n~ April 30, 1392, ~hich in turn is a continuation-in~part of United States Patent Application serial number ~8,1~3 filed on Jun~ 14, 1990 now abandoned, which in turn is a continuation in-part ol United Sta~es Pat~nt Appli~tion serial num~er 384,150 filed on July 21, 1989, whioh in turn i~ a ~ntinuation-in~part of United States P~tent Applio~tion s~rial number 273,685 filed on November 21, 1 g88, now U.~. Patent No.
4,907,383 WhiCh issued on March 13, 19~0.

This invention relates to the field of prefabricated wall, roof and floor panels. Particularly the panels have a multilayered plasti~ core wherein on~ of the layers provides for the bonding of ~ panel skin which may have an irregul~r surface confi~uration or a smooth surface to another layer of the plastic cor~. The other layer of the core may also have an irre~ular surface. The layer providing the bondin~ may be foamed-in-place and thereby will conform to the surface irregularities of both the skin and the foam core. ~he bonding l~yer is preferably a thermoset foam material.
The prefabricated w~ll, roof and floor panels rn~y further have incorporateci or en~apsulated therein additives which deter ant and insect infestation and additionally may act as a fun~icide and enhances the fire retardant characteristi¢$ of the panels, More particularly this invention relates to the encapsulation of ~ borate compound within the core material of single or rnulti-layered core prefab~ic~ted building panels. The multi~layered panels are as described in Appli~ant's copending application serial numbers ~76,9~0 and 384,150 and the sin~le layered panels are as described in ~, ~, . ,~

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a ~ s~ ~! 9 Applicant's U. S. Patents Numbers 4,907,383 a~d 4,833,855. The 3 panels so described may b~ fabricated in a novel w~y frorn smaller panel pieces, so as to continue the skin strength (both compression and tensile) and which panels rnay have incorporated novel means for more i gecurely, efficiently and economically joining such panels to form eith~r structural/load bearing walls or non-structural/non~lo~d `~ bearing walls which may be highly insulative with substantially no :d~ thermal bridges, The multi-l~yere~ pansl has a hi~hly insulative muiti~layered core loc~ted adjacent to on0 skin or ~Itern~tively !! located betwe~n two skins bonded to or otherwise rigidly affixed to the two outside ~urfaces of tha core, The core of the rnulti~lay~re~
panel has a plurality of core layers which may be of the same or of different foam plastic nlaterials, The l~yers of the ~ore located adjaGent to the panel skins provi~e a thermal barri~r for th~ middle or second core layer which midclle layer may be of a thermoplastic such as styrofoam and also may provi~e the means for bonding or se~urely ~ffixing the panel skins which may have an irregular sur~ace geornetry to the surface of the multi-layered core, whioh ~ore m~y also have an irregular surface geometry, The borate, whi~h is typically in the form of a powder ~ borate compound used h~s been TIM-~OR(~) a produot mar)ufactured by U. S. Borax Corporation), may be incorporated into all of the lay~rs of the panel. However, it is most important that the . b~rate he encapsulated within the first and the third layers that is, the layers adjacent to th~ skins of a panel having two skins.
The panels may be flat or planar or the p~nels may hav~ ~ ~owed configur~tion and when assembled in e~ge-to-ed~e relationship with cornplementary mating edges i.e., which edges abuttin~ly match the .-' edges of similarly configure~ ~djacent panels, form a bowe~ roof or a bowed wall of a ~tructure such as the bowed roof in a so called "~OW~ ROOF CAPE" or "BOW~D CAPE".
The p~nels further may have a ~kin or skins which ne~d not be ~lat. The skin or skins of the irnproved panels may he made from oorrugated metal, wood, plastic or any other material ~uited for suGh us~. The skin or skins may have a ~urface confi~urAtion similar to an "e~g crate" for example. Likewise, the middle or second layer of the .
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multilayer core may have an irregular surface shape. The important teature h~re is that the core of the panel when thermoset pl~s~i¢ is used as the material for at least one of the layers and p~rticularly the layer adjacent to the skin or skins also provided for the bondin~ or the affixing of the core to the skin even though the skin and/or the core has an irregular surfac0 such as is found on corrugated panels etc,. An avera~e thickness of the thermoset ~oam layer may ~e ~ny value but ~ill be ~ function of the ge~metry of the surface of th~ irr~gular surfaced skin which is borlcled to the core using the thermoset foam layer.
gESC~lPTlON OF ~HE PRIOBA~T

The rising cost of labor and rnaterials have rnade building construction ~nd especially the construction of homes increasingly more expensiYe. In addition the cost of heatin~ and cooling a buildirlg has increased many times over in rec~nt ye~rs. In orde~ to keep th~
cost~ of construction, heating, cooling ~nd maintenance withln reasonable limits and ther~fore a~forda~le to the general publio, innovations have been necessary. In part because of the availability ~f prefabrioated structure-wall and curtain-wall panels of the type ~liscussed herein and in ~pplicant's U. S. P~tents Nurnbers ~,907,38~
and 4,~33,855, there has been a return to the post and beam type of modular construotion vrhich lends itself to a prefabrication of the many construction components away from the con$truction site. By prefabricating and preouttin~ rnany of the components of the structure at a manufacturing facility, many procedures may be used to irn,oro~e the fabrication efficiency and improve the quality of the components as well as reduce the construction time.
Prefabricated panels that may or m~y not be load bearing ar~
provided at the construction site and are designed to be used with the post and beam construction. The panels which do n4t c~rry a load are sometimes referred to as curtain wall p~nels and can be used to rapidly enclosed the post and beam frarne. The exterior or outer skin of the panel is provided ready for siding to he applied and the insid~ or . ~
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inner ~kin of the panel is provided ready for ~pplication of any desired interior finish, Currently the panels, whether they are structure~wall panels ~loa~ bearin~) or curtain-w~ll panels (non-load ~earing~, are conneoted one to the other alor~g the vertical edges of the p~n~ls by what is referred to as splines or stud posts. These splines or ~tud posts unfortunately introduce thermal bridges. Further, the joint of adjacent wall so joined by the stud posts, whether by mechanical or by gluing means, do not continue Ihe stren~th of the panel skins. In U.S.
Pa~ent No. 4,~7~,~09 smaller than normal load bearin~ panels are ~hown assembled without the use of stud po~ts. Suoh ~n assembly requires that lhe panels have eith~r the foarn insul~tion extend beyond the p~nel skins or the panel ~kins extend beyond the foam insulative core. The two types ol panel ed~es can then be allernati~rely abutted and fastened, by gluein~ for example, to form a wall. It should be ~le~rly noted th~l the assembled wall does not provi~e for a panel or wail skin which has ~ontinuous strength from panel to panel, Prefabricated structure-wall and curtain-wall panels which provide the adv~ntages over the prior ~rt ~re d~fined an~ discussed in ~pplicant's U. S. Patent Number 4,833,855 Presently, homes which have bowed walls an~/or bowed roofs are constructed using, in the instan~e of the bowed roof, rafters which are cut, sawn or laminated to have the appropriate arc or radius to create the bowed roof configuration. The roof skin is then constructed over or between the rafterg using convention~l and well known ~onstruction methods. Likewise, the inner ~urface had to be linished if th~ inner s~r~ace of tho roof was to be a finished surface or a d~corated surface. Wher~ appropriate, insulation w~s al60 incorporat~d into the roof.
There are also available homes and/or structures which have roofs which are bowed inwardly or in other words concav~ inslead of convex. Again, the known methods of conventional Gonstruction require the use of a relatively complex framing system of ~oncave rafters et~. The roof skin is constructed simil~rly to the roof for the convex or bowed roof structure and similarly for a struotur~ having a domed roo~. The bowed panels defined and described in AppliGant's lJ.S.

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Patent Number 4,907,383 provide lhe advantages needed to construc the bowed roofs and walls of a building.
It would be advantageous to provide a multi-layered core prefabricated insul~tive buildin~ panel which would provid~ improved ~ire retardation, retard or deter insect infestation, ~nd would have skins regular or irreg~lar surfaced which are bonded to the core using the core material of the layer adjacent to the skin ~r skins and adjacent to the middl~ core layer.
It would also be advanlageous to provide a multi-la~ered core prefabricated in~ulative buildin3 panel which would not require the use of an ad~itional component such as a spline or stu~ post to attach panels to forrn a lar~er panel or wall. In addition to the stud posts being an additional component they also reduc~ the effective in~ulative property of the completed building bec~use they create thermal bridges. Thus the elimation of the stud post or splines improve~ the thermal efficiency of the completed ~uilding in addition to enhancin~ the construction efficiency and reducing the cost. In addition, it would be desireable to h~ve multi~l~yered core builc3ing panels similarly made but which would have a bowed configuration allowing for the construction with such panels of bowed walls, bowed/oonvex or dorned roofg and concave roofs (collectively ref~rred to herein as non-planar walls or non-planar roofs) witho~t th~ n~ed to fabricate, by lamination or by other well known means, bowed rafters and other similarly configured components which m~ke up the relatively complex framing systern. The advantages of bowed roofs and bowe~ w~lls are relatively obvious to ~hose of ordina~y skill in ~he art of home or buildin~ desigr) and ~onstruoti~n. Arnon~ som~ of the advantages are Increased livin~ space and permitting new ~esign varia'~ions with prefabricated panel ¢onstruction. Where the bowed multi-layered core prefabricated panels are structural panels, it is possible to conslruct ~ bowed roof or a bowed wall for ex~mple witholJt the need for bowed r~fters and a bowed wall stud cor~figuration thereby, for the bowed roof, increasing the useable space av~ilal~le on the g~cond and the third level of the buildin~.
Bowed non-structural prefabricated panels having proper joinin3 '~

2~9~8~9 systems incorporated therein could readily be used as clJrtain wall (non-stru~tural) panels o~ pla¢ed over bowed roof rafters ~nd would therby eliminate the construction step of insulatin~ the roo~ when the panel is providecl with a multi~layered insul~tive foam ~ore. Such panels which solve these problems are describe~ in Applicant's copendin~ Application Serial Number 384,150.
In United States Patent 4,37~,31~ there is described a prefabricated panel construction system using self-drilling thr~aded fasteners, met~l strips embedded in the p~nels to provide anchors for th~ threaded fasteners an~ specially adapted unsulatin~ member along one ed~es of each panel t~ provide mechanical support. In IJnited States Patenl 4,625,472 there is described a lightweight structural building panel having a shape cornpatible for use in assembling a geodesic dome structure. It is irnportant to note that the p~nels do not have a bowed ~onfiguration and could not be used in the manner described herein.
It is also important to not~ that rn~ny of the prefabricated building panels currently in use have, as a core ~naterial, styrofoamlstyrene or oth~r forms of therrnoplastic fvam. The core of these panels melts Yery qulckly in the presence of high temperature ~nd as a res~lt the panels lose their structural inte~rity very quickly.
The pan~ls described in applic~nt's copendin~ application serial number 273,~85 and applicant's Patent No. 4,833,855 have a homo~eneous insulativ~ core material, and where the core material is a thermosetting material such a urethane the p~nel cores do not melt when exposed to high heat. However, the panels are more expensive and heavier th~n panels having a thermopl~stic c~re. Also, in order to foarn~in-place the urethane foam and to also use the urethane ~oam to bond the skin or skins to the homogeneous ureth~ne core, it is necessary to heat the foam for a ~airly long tlme. The panels of the present invention ov~r~orne the disadvanta~es of these prior ~rt panels. The m~lti-layered core buildin~ panel provides the thermal protection, proYides th~ fastening means i.e., the bondin~ and irnproves the stren~th of the p~n~l and the sta~ility o1 the p~nel skins.
Additionally, sinc~ the layers adj~cent to the skins does not . .

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, -, constitute the en~ire core, the time to ~oam and i~ond the skin and the second or inner core layer is reduced. A panel accordin~ to the present invention ~ould have a metal skin including corrugated metal, a therrnosetting foam plastio ~or~ layer bonded to the skin and to a second c~re layer of a thermoplastiG foam. The thernlosetting ~oam layer would provide an effective therntal barrier between the metal skin and the styrofoam core. i.8., it would extehd th~ p~riod of time at which the styrofo~m core would melt and become structurally unstable in the presence of high heat.
A~sociated vvith all of ~he prefabricated construction panels discussed al~ove there is th~ problem of ant infestation~ While standard methods may be employed to elimin~te the presence of antg and termites and other insects which ~ttack wooden structures, where prefabricated panels are used it is difficult to introduce pesticides and fun~icides into the core re~ions of the panels. It woul~ be extremely advantageous to be able to incorporate or enc~psulate a material or compound into the core of the panel which would de~er ~he infestation of insects.
SUM~ Y OF THE lN~l~NTlON

The present invention, in its most sin~ple embodiment, is direoted to ~ prefabricated building panel, sometimes referred ~o ~s a stress &kin panel irl whiGh the thermoset foam m~terial of ~ multilayer core is use~ ~s the bonding material between the skins and the core. Th~
core may be comprised of a single layer ~r may have mwltiple layers of material and into which core may be incorporated, or en~apsula~ed, borates in the form of borate compouncls in an amount (typically between about 2 wei~ht percent and ~bowt 10 weight percent~ which results in a material which deters the ~ntry of and the infestation of ants and ot~er insects thereby enhancing an~ improving the usefwlness of such prefabricated building panels. The addition o~ the borate compound has al~o been found to ~ct as a fun~icide and is ~Iso flame retardant . Borate may be added, if possible, into th~ core material of any known prefabricated ~onstruction/buildin~ panel. I~owever, it is ",,~

2~.3~9('~'`3 most advantageous and effective if the borate is added durin~ the f~brication of the core of the panel especially the p~nels defined by Applioant's U.S. Patents 4,8~3,855 and 4,907,383 and the multi-layered panels defined in Applicant's copending Applic~tion Serial Number 384,150 wherein the layer or layers are typically o~
uniform thickness or a thickness which may vary or taper over the L1`~ length a~d/or the width of th~ panel and which m~terial ig bonded to t least one ~djacent skin. The cornbination of the core and skin is ,~ preferably but not necessarily basically rectangular in shape and it may be bowed frorn one shorter edge to the other sh~rter edge or trom one longer ed~e to the other longer ed~e. The edges of the p~nels are configured to abuttingly m~t~h corresponding edges o~ slmilarly confi~ured panels, The first layer of ~he multi-layered core is a thermo~etting foam plastio such as lJrethane, phenolics, isocyanurate or other Gross-linked or thermoset type of foam. The second layer may be of the same ~'~ material as layer one in which case layer lwo may be pre~rnade into typically a rectangular sheet form and placed into position so that when the first layer is foamed the second layer becomes securely affixed to one surface oF the first layer and the other surface of the first iayer ~ecurely ~ttaches throu~h the bo~ding of the thermoset plastio to the surface of the skin eYen when the skin surface bein~
`~J bonded is irregular i.e" non-flat ~nd even when the surface o~ the ~econd layer is irregular. Where there are three layers, the first and the third layers are adjacent to th~ skins and the second layer in positioned between the first an~ the lhird, The first and third layers also provide the bondin~ or the rneans for s~curely a~fixin~ the skins to the multi-layered core and provicie a thermal shiel~ and thereby extends the life of the panel when exposed to a high temperature environrnent. The bor~te, which is typio~lly in the ~orm of a powder (a borate compound used has been TIM-BOR~', Disodium Ootaborate Tetrahydrate, a product manu{actured by U. S. Borax Corporation)~ may be incorporated into all of the layers of the panel. However if the ~! Borate is used, it i$ most important that the borate be eno~psulated within the first and the third layers that is, the layer6 adjR~ent to the ~ ...., ~
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ski~s of a pan~l havin~ two skins.
In the event that thicker ~nd larger prefabricated insulativ~
panels are needed, the use of the multi-layered core of this invention permits the fabrication of su~h panels. The second layer of the core can be preformed and positioned between the skirls. Since the first and third thermosetting foam layer do not form the ~ntire aore thickness it is e~sier ~nd more feasible to f~am~in~place thesb two layers effeGtively bonding the skins, whether they be flat surfaced or irr~gular gurfaced, to the multi~layered core. There is no l~ss in the irlsulative quality of the panel ~nd in fact the skin stability is enhanced.
It is important to n~te that, when the panels are assembled t~
form a wall or a roof assembly, the strength of the skins are continued from p~nel to panel ~ithout the need for stu~ posts or the like. When the surlaces of the joints are ti~htly joined using a faste~ing mean~, such as tor example glue, the tensile an~ compression forces are continued through th~ joint region from panel skin to panel skin and the wall has the ~haracter of a single continuous surface.
It is an object of the invention to provide an improved prefa~ricated building panel having a core of foanl plastic material ~nd having two opposed surfaces, the cote havin~ edges defining thereby the si~e of the panel and at least one, skin each having an average predetermined thickness, a preselected surf~Lce oonfigur~tion and each skin sized subst~nti~lly the same as and securely affixed to at least on~ of the surfaces the improvement comprising: between about 1 wei~ht percent an~ about 20 weight percent of a borate ~ompound encapsuiated within the foam plasti~ material. The ~oam plastic mate~ial is preferably a thermoset foam plasti~ but m~y be a thermopiastic foam plastic. Where thermoset foam mat~rial is used the bonding of the core to the skin i$ affected by the thermoset material itself.
It is a primary object of th~ invention to provide a prefabricat~d buildin~ panel comprisin~ a core of a plurality ot layers of foam plastic material the core comprising a first layer being ~ thermoset type of foam plastic which may have bet~een about 1 weight percent !, ~

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and about 20 weight percent of a borate compound encapsulated therein and having two opposed surfaces, one of the two opposed first layer surfaces securely affixe~ by the bonding provided by the thermo~et foarn of the first lay0r to a first surface havin~ a presele~ted surface configuration of a seoond foam plastlc layer the core having ed~es definin~ thereby the si~e of the panel; and a skin havin~ an aver~ge predetermine~ thickness, a preselected surface configuration and sized substantially the same as and ~eourely affixed by the bonding provided by ~he thetrr oset foam of the first layer ta ~nother of the first layer surfaces.
Another primary object of the invention is to provide ~
prefabricated building panel comprising: a core of a plurality of laye~s of foam plastic material, at least one of the plur~lity of l~yers of fo~m plastic materi~l which may have betw~en a~out 1 ~ei~ht percent ~nd ~bo~t 20 wei~ht percent of a borate compoun~ en~apsulated therein, the core comprisin~ ~ firs~ layer being thermoset foam plastic and ha~/ing two opposed surfaces, one of lhe tw~ opposed ~irst layer surfaces securely affixed by the bondin~ provided by the thermoset foam of the first layer to a first surface having a preselected surface configuration of a se¢ond foam plastic layer, a thir~ layer of thermoset foam plastic rnaterial h~ving two opposed surfaces one third layer surface securely ~ffixed by the bondin~
provided by lhe thermoset foam of the third layer to a second surface havir~g ~ preselected surface configuration of the second foam plasti~
layer, the oore having two opposed and s~bst~ntially ~/ertical core edg~s, and two oppose~ and substantially horizontal csre edges defining thereby the size of the panel; an inner skin havin~ arl average predetermined thickness and sized substantially the same as a~d securely ~ffixed by the bonding providecl by the thermoset foam of the third layer to another of the third layer surface; and an outer skin having an average predetermined thickness ar~d sized substantially the same as and securely affixed by the bondin~ provided by the thermoset foam of the first l~y~r to another ~f th~ first layer surface.
A f~rther prirnary object of the presen~ invention is to provide the prefabri~ated building panel wherein the second ~o~m plastic layer , ~
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x,~- , 2 0 9 .'3 ~ f3 f3 is a thermoset foam plastic. -A y~t further primary obj~ct of the present invention is to provide the prefabricated panel described wh~rein the inner skin an~/or the outer skin is material selected from waferboard, oriente~
strand board, fiberboard, plaster board, sheetrock, wood p~nel, wire, wire reinforced paper, pressboard, particle bo~rd, plywood, metal, plastic, ~iber rein~orced concrete, poly-con'crete ~ncl corrugated nletals woods and plastics, alone or in mul~ilayered ~ornbinations thereo~.
~ still further primary obje~t of the present invention is to provide panels as described wherein the seGond foam plastio layer is a thermoplastic ~oam plastic such as fo~ example styrofoam.
Yet another primary object of the present invention is to provide panels as described wherein the first and third thermoset fo~m pl~s~ic layers have an average thickness of between ab~ut 11~ inch ~nd ab~u ~ inch and each may have between about l wei~ht percent ~nd about ~0 weight percent of a borate oompound encapsulated therein.
Another object of the present invention is to provi~e a method for det~rring the in~estation of a prefabricated building panel by ant~ and other wood affectin~ insects by enoapsulating ~ borate compound into a core material ot the building panel the cors being a foam plastic, the method comprising: addin~ be~ween abou~ l wei~ht percent and about ~o weight percent of the borate compound into at least one ~omponent of the foam plastic; agitating to evenly dispers~ th~ borate compound thl oughout the at least one component ()f the foam plastic to form a first mix; rapidly and evenly interspersing a predetermined amount of the first mix with a predet~rmined amount o~ remaining ~omponents o~
th~ foam plasti~ forming a second mix which upon curin~ l~rms the foam plastic; and causing the second mix to cure onto and be attached to at least one skin of the buildin~ panel. The foam plastic core material may be a thermoset foam plastio ~nd the at least one component i8 substanti~lly polyol and the remainin~ component i substantially isocyanate. The predetermined amounts of the first mix and the rem~ining components being abo~t e~ual. AlternatiYely the foam plastic core material may be a thermoplastic ~oarn pl~stio , ,~
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selected ~rom the group consisting of extruded styrene, expanded polystyrene and poly-vinyl-~hloride and the at least one component is substantially a thermoplastic resin prior to th~ forming of beads which ~eads ~re used to form the thermoplas~ic ~oam ~ore th~re~y encapsulating the borate compound within the thermoplastic f~am COrB.
These and further objects of the present invention will become apparant to those skilled in the art after a study of the present disclogure of the Invention.

" .,, BR IE F DESCR.IPl ON OF THE~ DRAWIN GS

FIG. 1 is a perspe~tive view of the multi-layered core prefa~ric~ted building panel having an outer skin and an inner skin according to the present invention;
FIG. 2 is a perspectiYe view of tl~e multi~layered core prefabricated building pan~l having one skin acoording to the present invention; ~nd Fl~. 3 is a perspective view of the multi"layered core prefabricated building panel having an outer ~kin which has an irregular surf~ce and illustrating a first layer of the core with an average thickness foamed in~pla~e thereby affixing by bondin~ the outer skin and the çore, and also illustrating an inner skin having a smooth surface;
FIG. 4 is a perspective view of the multi-layered core prefabricated building panel havin~ an outer skin which has an irregular surface and illustrating a first layer of the ~ore with ~n average thickness foamed in-place th~reby affixing by bonding the outer skin an~ the core, ~nd also illustrating an inner ~kin h~vin~ Rn irregular surface;
FIG. 5 is a perspective view o~ the multi-layered core prefabricated buildin~ p~nel h~ving an outer skin which has an irre~ular surface and illustrating a first layer o~ the ~ore with a basically constant thickness foamed in-plaoe ther~by affixing by bonding the outer skin and the irregular surfaced middle core layer, and also~ illustr~ting ~n inner ~kin havin~ a smooth surface;
FIG. 6 is a perspectiv~ vie~ of the muiti~layered core prefabricated buildir~g panel havin~ irregular surf~ed outer ar~d inner skins which has an irregular surface and illustrating a first and third layer of the core each with basically constant thickness toamed in~place thereby affixing by bonding the irre~ular surfaced outer and inner skins ~nd the irregular surfaced middle core layer;
FIG. 7 is a perspe~tive view of the rnulti-layered core pr~fabricated buil~ing panel havin~ an outer skin whi~h is made up of a i J % ~

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combin~ion of skins with different skin surface ~eometri~s and which has an irre~ular surface ~iiffersnt from that illustr~te~ in Fig 3 and otherwise the panel is as the panel of Fi~. 3; and ~ . 8 is a perspective view of the multi^layered core prefabricated building panel having an outer skin which is made up of ~
combination of skins with different skin surface geometries and which has an irre~ul~r surface different from that illuGtrated in Fi~. 5 and ~therwise the panel is as the p~nel of Fig. S.

~ESCRlPT101~ )F T~IE PR~FE~RED EMBOl~ lENT~}
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ln order to more clearly describ~ and disclose the inv~ntion, building panels having foam plastio types of core materials will be u~ed. The types of panels are those illustrated in Fi~ur~s 1-~ which are meant to be only representativ~ of the types ~f panels into which the invention may be incorporated. The panels whi~h wiil be used as example panels are described as havin~ subst~nti~lly uniform thickness, rectangular in shape, a multi-layerecl foam plastic insulative core of uniform thickness and bonded to one or to two skins.
Clearly, the core need not b~ multi-layered. ~he ~ore of the panel, ~hether multi-layered or of a single layer of material, may b~ m~cle out of thermopl~stio foams such as expanded polystyrene (E PS), styrofoam, extruded s~yrene, PVC or phenolics, urethane, or any of the variety of isocyanurate plastic foams. The skins will be shown made of typically one of the standard materials but it should be noted that the skin or the skins may be made from cornbinations of skin materials and the skin or skins may have an irregular surface and still ~e bonded by the thermoset foam where such rnaterial is use~ as the ~orP or as a layer of a multilayer core. The combinalion may bs and most Iypically will be in laminated or layered forrn. But clearly there ~ould ~e a mixlure ~f materials in ~thsr than layered form where the materials would so permit.
Referring now to the embodiment shown in Figs. 1 which ill~strates a pref~bricated panel 10 having two (2) skins 22 ~nd 24 and a multi-layered core 12 having a first layer 14, and s~Gond layer ~9~Q~

16 and a third layer 18. Typically the ~irst ~nd the third layer 14 and 18 will have TIM-BO~ encapsulated within each of these foa~ yers;
howe~er, it may be advantageous, depending upon the applicatiorl ~f the panels, to have bor~te with only one layer or within all thre~ layers The kin 24 is ~ecurely affixed at the inner surface to arlother first layer surface 13. The one first layer surface ^i 5a is affixed to first surface 15 of the second layer 16. The second surface 17 of second layer 15 is affixed or boncled to one surface 17a of a third l~yer ~8.
The other surfa~e 1g of the third layer is affixed or bonded to th0 inner surFace of the inner skin 22.
The embodimen~ shown by Fi~. 2 is a prefabricated panel ~0 which is similar in ev~ry respect to the panel 10 except th~t there is only one skin 24 and the core 12 comprises a first layer 14 and a second layer 16 and typically the first layer 14 would have the borate compound encapsulated within. However, it is also within the scope of the invention to enoapsulate the borate compound within both the first and the ~econd layers 14 and 16.
~ eferring now to the embodiment shown in Figs. 3 and 4 whi~h illustrates a prefabricated panel 10 having two (2) skins, ~ flat inner skin 22 ~nd an irreg~ r surface~ outer skin 24a of Fig. 3, an irregular inner skin ~2a and an irregular surfac~d outer skin 24a of Fig. 4 each having a multi-layered core 12 having a first layer 14, and second layer 16 and a third layer 18. Typically the lirst ar~d the third layer 14 and 18 will have TIM~OR(~9 encapsulated within each of these f~a~
layers; however, it may be ~dvantageous, depending upon the application of the panels, to have borate with oniy one l~yer or within all thre~ layers. Th~ skin 24à is s~curely affixed at the inner surface to another first layer surfa~ 13. The one first layer surface 1 5a is affixed to first surface 15 of the second layer 16. The second surfa~e 17 of second layer 16 is affixed or bonded to one surface 1 7a of a third layer 18. The other surface 1~ of the third layer is affixed or bonded to the inner 6urf~se of the inner skin 22.
P~eferring now t~ the embodirnent shown in Figs. 5 ~nd 6 which illustrates ~ prefabricated panel 10 having t~ (2) skins, a flat inner skin ~2 an~ an irre~ular surfaced outer skin 24a of Fig. 3, a~ irreg~lar 2 ~ 9 ~
.~

,1 inner skin 22a and ~n irre~ular surfaced outer skin 24a o~ Fig. 4 each .j having a multi~layered core 12 havin~ a first layer 14, and second layer 1~ and a third layer 18. In the embodiments of th0se Figs. 5 and 6 first layer 14 bonds to both irregul~rly shaped skin 24a ~nd to an irregular first surf~ce 15b of se~ond layer 16 for Fig. 5 ~nd third layer 18 b~nds to the irregular surfac~ 17b of layer 16 anci to irre~ular inn~r surface oi inner skin 22a sho~n in Fi~. 6. Typically the first anci the thir~ layer ~i4 and -i8 will have TIM-B:)R~) en~apsulated within e~ch of these foam layers; however, it may be a~vanta~eous, depending upon the application of the panels, to have borat~ with only one layer ~r within all three layers. The skin 24a is se~urely affixed at the inner surface to ~nother first layer surfa~e 13. The one first l~yer surface 15~ is affixed to firs~ ~urface 15 of th~ second layer 16. The ~econci surface 17b of second layer 1~ is affixed or b~nded to one surfac~ 17a of a third l~yer 18. The other surface 1g of the third l~yer is affixed or ~onded ~o the flat inner surface of the inner skin ~2 as in Fig. 5 or irre~ular inner ~urfac~ of irregular inner skin 2~a as in FiJ. 6.
Figs. 7 and 8 are p~nels similar to those described relative to Fi~. 3 ~ 6 with slmply a different surface geometry for the skins.
In the preferred embodiment of the invention, a borate compound such as TIM-BOR~) is encapsulated within the core portion of the panels 10 and 30. These panels have an insulative~ typiG~lly foam plastic, multi-layered core 12 which core 12 h~ ~ub tantially uniform thickness bonded to an outer skin 24 as in Fig. ~ and to an outer ~kin 24 and an inner skin 22 as shown in Fig. 1 ~nd has substantially an average uniforrn thickness bonded to an outer skin 24a a~ in Fig. 3. The typical material from which the ~irst and the ~hird Iayers are made is ureth~ne. However, any thermosetting fo~m, that is foam which does not melt when exposed to hi~h temperature, may be -¦ useci. So~ne thermosetting foams have a temperature at which foaming~ is triggered and there may be advantage~ to using such f~ams when if~ m~king the panels of this invention. Further, some thermosettin~
foams provide for better bonciin~ to the surfaces 15 and 17 of second layer ~ and to the inside surfaces of skins 22, 22a, 24 and ~4a. The exact formulation of thermosetting foam for use in Gore 12 will .~
2a~0~

depend uporl m~ny factors. Howe~er, all of such foams are within the scope of ths present invention.
It is of ç~urse un~erstood that the second layer 16 of the core 12 may be material other than an insulative material such as for ~xampl~
a paper honeycomb or any other material which could fl~nction as a core for the panels. However, the preferred material o~ 5eoond layer 1~ is a foam plastic which is hi~hly insulative such as styrofoam or styrene or extruded polystyrene The o~ter skin 24 may be material, preferably, such as plywood, waferboard, particle board or oriented s~rand board or material over which siding or roof shingle~ rnay be attached. The outer skin may also be waferboard, oriented strand board, fiberbo~rd, plaster bo~rd, sheetro~k, wood panel, wire, wire rein~orced paper, pressboard, particle board, plywood, m~tal, plastic, fiber reinforced concrete, poly-concrete and irregularly shape~l surf~ces such as ~or example corrugated or egg-crate shaped surfaces of all of the materials listed including metals woods ~nd plasti~ The Tnner skin ~2 may be, preferably, gypsum board, ply~vood or other malerial which ~ay be used ~or the interior wall or ceiling cov~ring or as the base for the finished interior wall or ceilin~ but clearly may be of other regular or irre~ularly surfaced materials.
The pan~l is usually fabricated havin~ a ~enerally rectan~ular configuration. The edges de~in~ the si~e of the p~nel 10. The skins 22, 22a and 24 are typically attached to the core 12 when th~ ~ore 12 is falsrl~ated~ After the panel 10 or 30 is fabricated, a joint may be machined, or mol~ed or cut into the appropriate edges of the panel 10 or 30 in such a manner so tha~ when p~nels are assembled to~ether in edge-to-edge relationship the adjacent edges of the assembl~d panels abuttingly match. Where inthe-field assembly is to be used a ~nicro encapsulated adhesive may be applied to at least one of the edges of the panels 10 or 3~. Wpon ~ssemblin~ panels 1~ or 30 in order to form walls, or roofs it has been found that the captured ~carf joint permits the effectiv~ a~sernbly of panels 10 or 30 using only the ~dhesive. It has been observed that bec~use of the special angles and unique characteristics of the ~aptured scarf joint, ~h~ panels 10 or 3~ b~ing joined, ~re captured, very easily aliynecl and securely held in postion.

~, ,.

2 ~ 9 9 g (~ e3 In addition to the larger bonding area proYided by th~ captured scarf joint the joint is not tight until it is completely ~losed thereby c~using a very tight and continuous,from panel to adjacent panel~ ir~ner skin 2~ and oute~ skin ~. That is to say that the inner and the outer skins of joined panels being tight an~ continuous is meant to ~onvey the notion that the skin strength from panel to panel appears or ~ehaves as a continuous skin without joints would behave from a structural and a strength standpoint.
The method used in making the core material with the bor~te compound encapsulated within is substantiaily as follows~ dd between about 1 weight percent and about 20 weight percent of the borat~ compound into at least one component of the fo~m plas~ic and where isocyanurate fo~ is being used the borate is added to the poiyol component; (2) the combination is stirre~ or a0itated to e~eniy disperse the borate compound throughout the polyol component of the foam plastic; (3) ~his ~irst rnix is r~pidly and evenly interspersed in substantially eqllal amollnts by weight with the remainin~ components of the toam plastic, which in the c~se of an isocyanurate foam is isocyanat~, formin~ a s~cond mix which upon curing forrns the foam pl~stic; and (4) this second mix is caussd to cure usin~ catalysts ~r~d methods well known to those of ordinary skill and the curing is caused to take place onto and be attached to at least one skin of the building panel. Alternatively the foam plastic core material may be a thermoplastio foam plastic selected from the group consistin~ of extruded styrene, expanded polystyrene and poly-Yinyl-chloride and the borate compound is mixed with a thermoplastic resin prior to the forrning of beads which beads are used to ~orm the foam core thereby encapsulating the borate compound within the thermoplastic foam core. The plastic beads having the borate encapsulated within may be uged to produce the extrudecl styren~, the expanded polystyrene ~nd ~th~r types of thermoplastio foam products useful as core material for prefabricated building panels. It should be not~d that the borate could be introcluced into the resin before or during the expansion or the extrusion process. It is irnportant only that the bor~te b~
encapsulated within the basic foam and not simply distributed along ~9~
i I

the boundaries of beads which form, for example, a styrene sheet of material. Vthere the borate is at such boundaries, moisture very quickly reduces the effectivenes~ of the borate as an inseot deterrent within the building panel It is thought that the prefabricated wall, roof and floor panels wherein the material of the core is us~d to provide bonding of the core layers and the bonding o~ the multilayere~ core to the skin or skins which skins may have any preselected surface g~ometry and which may have inc~rporated or encapsul~ted within any or all of the layers of the core additives which cieter ant and inse~t inf~station and additionally may act as a fungicide ancl improve the flam~ retardant ~haracteristics of ths panel and more p~rticularly the additlon of borate to the core material of improved single or multi-layered core prefabricated building panels and m~ny of its att~ndant advanta~es including its usc in making the panels more flame an~ smoke suppressing, will bo understo~d from the foregoing des~ription and it will be apparent that various changes may be made in the form, composition of compounds construction and arran~ement of the parts and oompoun~s thereof without departin~ from the spirit and scope of the invention o~ s~crificing all of its material advantages, the form hereinbefore described being merely ~ preferred or exemplary embodlment thereof.

.,,", ~ .

r.~

Claims

1. A prefabricated building panel comprising:
a core of a plurality of layers of foam plastic material, said core having two opposed and substantially vertical core edges, and two opposed and substantially horizontal core edges defining thereby the size of said panel, said plurality of layers comprising a first layer being thermoset foam plastic having two opposed surfaces, one of said two opposed first layer surfaces securely affixed by bonding to a first surface of a second foam plastic layer;
a skin having an average predetermined thickness, a preselected surface configuration and sized substantially the same as and securely affixed by bonding to another of said first layer surface; and means for said bonding of said first layer surface to said first surface of said second foam plastic layer and said bonding of said another of said first layer surface to said skin is said thermoset foam plastic first layer.

2. The prefabricated building panel according to claim 1 wherein said second foam plastic layer is a thermoset foam plastic.

3. The prefabricated building panel according to claim 1 wherein said second foam plastic layer is a thermoplastic foam plastic.

4. The prefabricated building panel according to claim 3 wherein said skin is material selected from waferboard, oriented strand board, fiberboard, plaster board, sheetrock, wood panel, wire, wire reinforced paper, pressboard, particle board, plywood, metal, plastic, fiber reinforced concrete, poly-concrete and corrugated metals woods and plastics.

5. The prefabricated building panel according to claim 3 wherein said skin is material selected from a layered combination of at least two of the following; waferboard, oriented strand board, fiberboard, plaster board, sheetrock, wood panel, wire, wire reinforced paper, pressboard, particle board, plywood, metal, plastic, fiber reinforced concrete, poly-concrete and corrugated metals woods and plastics.

6. The prefabricated building panel according to claim 2 further comprising at least one of said core layers having between about 1 weight percent and about 20 weight percent of a borate compound encapsulated therein.

7. The prefabricated building panel according to claim 3 further comprising at least one of said core layers having between about 1 weight percent and about 20 weight percent of a borate compound encapsulated therein.

8. A prefabricated building panel comprising:
a core of a plurality of layers of foam plastic material, said core having two opposed and substantially vertical core edges, and two opposed and substantially horizontal core edges defining thereby the size of said panel, said core comprising;
a first layer being thermoset foam plastic and having two opposed surfaces, one of said two opposed first layer surfaces securely bonded to a first surface of a second foam plastic layer;
a third layer of thermoset foam plastic material having two opposed surfaces one third layer surface securely bonded to a second surface of said second foam plastic layer, means for said bonding of said first layer surface to said first surface of said second foam plastic layer and said bonding of one third layer surface to said second surface of said second foam plastic layer is said thermoset foam plastic first and third layer;
an inner skin having an average predetermined thickness, a preselected surface configuration and sized substantially the same as and securely affixed by bonding provided by said thermoset foam third layer to another of said third layer surface;
an outer skin having an average predetermined thickness, a preselected surface configuration and sized substantially the same as and securely affixed by bonding provided by said thermoset foam first layer to another of said first layer surface.

9. The prefabricated building panel according to claim 8 wherein said second foam plastic layer is a thermoset foam plastic.

10. The prefabricated building panel according to claim 8 wherein said second foam plastic layer is a thermoplastic foam plastic.

11. The prefabricated building panel according to claim 9 wherein said inner skin and said outer skin each is material selected from waferboard, oriented strand board, fiberboard, plaster board, sheetrock, wood panel, wire, wire reinforced paper, pressboard, particle board, plywood, metal, plastic, fiber reinforced concrete, poly-concrete and corrugated metals woods and plastics.

12. The prefabricated building panel according to claim 10 wherein said inner skin and said outer skin each is material selected from waferboard, oriented strand board, fiberboard, plaster board, sheetrock, wood panel, wire, wire reinforced paper, pressboard, particle board, plywood, metal, plastic, fiber reinforced concrete, poly-concrete and corrugated metals woods and plastics.

13. The prefabricated building panel according to claim 9 wherein said first and third thermoset foam plastic layers have an average thickness of between about 1/8 inch and about 1 inch and at least one of said first and third thermoset foam plastic layers having between about 1 weight percent and about 20 weight percent of a borate compound encapsulated therein.

14. The prefabricated building panel according to claim 12 wherein said first and third thermoset foam plastic layers have an average thickness of between about 1/8 inch and about 1 inch and at least one of said first and third thermoset foam plastic layers having between about 1 weight percent and about 20 weight percent of a borate compound encapsulated therein.

15. An improved prefabricated building panel having a core of foam plastic material and having two opposed surfaces, said core having edges defining thereby the size of said panel and at least one skin each having an average predetermined thickness, a preselected surface configuration and each skin sized substantially the same as and securely affixed to at least one of said surfaces said improvement comprising: between about 1 weight percent and about 20 weight percent of a borate compound encapsulated within said foam plastic material.

16. The improved prefabricated building panel according to claim 15 wherein said foam plastic core is a thermoset foam plastic and said thermoset plastic provides said bonding of said skin to said core.

17. An improved prefabricated building panel according to claim 15 wherein said foam plastic core is a thermoplastic foam plastic.

18. An improved prefabricated building panel having a core of a plurality of layers of foam plastic material said core comprising a first layer being thermoset foam plastic and having two opposed surfaces, one of said two opposed first layer surfaces securely affixed to a first surface of a second foam plastic layer said core having edges defining thereby the size of said panel and a skin having an average predetermined thickness, a preselected surface configuration and sized substantially the same as and securely affixed to another of said first layer surfaces said improvement comprising: sing said first layer as means to securely affix by bonding said skin to said second foam plastic layer and wherein said skin is material selected from waferboard, oriented strand board, fiberboard, plaster board, sheetrock, wood panel, wire, wire reinforced paper, pressboard, particle board, plywood, metal, plastic, fiber reinforced concrete, poly-concrete and corrugated metals woods and plastics and between about 1 weight percent and about 20 weight percent of a borate compound encapsulated within at least one layer of said plurality of layers of foam plastic material.

19. An improved prefabricated builing panel having a core of a plurality of layers of foam plastic material said core comprising; a first layer being thermoset foam plastic and having two opposed surfaces, one of said two opposed first layer surfaces securely affixed to a first surface of a second foam plastic layer, a third layer of thermoset foam plastic material having two opposed surfaces one third layer surface securely affixed to a second surface of said second foam plastic layer, said core having two opposed and substantially vertical core edges, and two opposed and substantially horizontal core edges defining thereby the size of said panel; an inner skin having an average predetermined thickness, a preselected surface configuration and sized substantially the same as and securely affixed to another of said third layer surface; an outer skin having an average predetermined thickness, a preselected surface configuration and sized substantially the same as and securely affixed to another of said first layer surface said improvement comprising: using said first layer as means to securely affix by bonding said skin to said second foam plastic layer and wherein said inner skin and said outer skin each is material selected from waferboard, oriented strand board, fiberboard, plaster board, sheetrock, wood panel, wire, wire reinforced paper, pressboard, particle board, plywood, metal, plastic, fiber reinforced concrete, poly-concrete and corrugated metals woods and plastics and between about 1 weight percent and about 20 weight percent of a borate compound encapsulated within at least one layer of said plurality of layers of foam plastic material.

20. A method for deterring the infestation of a prefabricated building panel by ants and other wood affecting insects by encapsulating a borate compound into a core material of said building panel said core being a foam plastic, said method comprising:
adding between about 1 weight percent and about 20 weight percent of said borate compound into at least one component of said foam plastic;
agitating to evenly disperse said borate compound throughout said at least one component of said foam plastic to form a first mix;
rapidly and evenly interspersing a predetermined amount of said first mix with a predetermined amount of remaining components of said foam plastic forming a second mix which upon curing forms said foam plastic; and causing said second mix to cure onto and be attached to at least one skin of said building panel.

21. The method according to claim 20 wherein said foam plastic core material is a thermoset foam plastic and said at least one component is substantially polyol and said remaining component i substantially isocyanate, said predetermined amounts of said first mix and said remaining components being about equal.

22. The method according to claim 20 wherein said foam plastic core material is a thermoplastic foam plastic selected from the group consisting of extruded styrene, expanded polystyrene and poly-vinyl-chloride and said at least one component is substantially a thermoplastic resin prior to the forming of beads which beads are used to form said thermoplastic foam core thereby encapsulating said borate compound within said thermoplastic foam core.